I actually don't carry any life insurance anymore. Sacrilege, I know. But DD is now 17, and I have no spouse (never did - I know, another sacrilege - what can I say, I don't follow social norms). The small amount of insurance I get for free through work, plus my assets, would give DD right about 10x my annual salary. That should be enough to see her through college, and get her setup in life on her own. The rest will have to be up to her!
Now if I'm still alive once she's out of college, well then, it's time for me to enjoy retirement! Who knows what will be left for her
But really, if you are worried about Alzheimer's or other issues requiring expensive care eating up your savings and leaving nothing for an inheritance, you might be better off to look at long-term care insurance. It's not a fix-all, but it would help. My plan is to get a policy once I'm done paying for DDs college. My mother had Alzheimer's, and we managed with home care for many years. But in a final twist of fate, she actually died of lung cancer that was undiagnosed until the end stages - you just never know what will happen!